Official Luthiers Forum!

Owned and operated by Lance Kragenbrink
It is currently Sat Jul 26, 2025 2:15 am


All times are UTC - 5 hours


Forum rules


Be nice, no cussin and enjoy!




Post new topic Reply to topic  [ 8 posts ] 
Author Message
 Post subject: Mortise and Tenon joint
PostPosted: Tue Feb 10, 2009 7:10 pm 
Offline
Walnut
Walnut

Joined: Thu Mar 13, 2008 8:58 am
Posts: 6
Location: Haileybury, Ontario, Canada
Hello,
When making a mortise and tenon joint ( for a Fleta ); the angle will no longer be 90 degrees to the body because of the 2 to 3 degree of forward lift create by the neck. How do you accurately mark this slight change prior to making the joint.
Ronald


Top
 Profile  
 
PostPosted: Wed Feb 11, 2009 2:54 pm 
Offline
Koa
Koa
User avatar

Joined: Thu Mar 30, 2006 4:33 am
Posts: 1518
Location: Canada
I have been wondering about this also as Im fast approaching this step myself - only with a dovetail joint -
Without hijacking this thread - I was hoping someone could respond to my query as well -
This is the way I thought of it-> mabye it applies to both M&T and dovetail operations Im not sure....
nearest I can figure is once the 12th fret location is established on th fb - to measure 90deg off thefretboard plane, then (or simply only) a 2deg line perpendicular to the fretboard plane at the 12th fret - then cut in on the 2 deg line to the outter edges of the dovetail outline - and trim the dovetail outline to leave the dovetail blank (i.e. hog off some of the waste wood) leaving enough to rout the dovetail (tenon)
Is this right? am I missing something or should I proceed this way?
PS Im using the Woolson jig - so once the preliminary setup is done Ill be using the jig to rout the actual joint ....
Cheers
Charlie


Top
 Profile  
 
PostPosted: Wed Feb 11, 2009 3:15 pm 
Offline
Old Growth Brazilian
Old Growth Brazilian

Joined: Tue Dec 28, 2004 1:56 am
Posts: 10707
Location: United States
I am going to show my ignorance here but what is a "fleta"? Regardless I use 1.5 degrees of "design" back angle in my necks I say design because each body requires flossing of the heel cheeks to properly fit the neck to bridge relationship as well as centerline relationship so the final out come may be 1.55 or 1.25 degrees neck angle based on that particular body.

Now how do I get my heel cheek at 1.5 degrees? I cut the cheek cut at a 1.5 degree angle on both sides of heel to tenon depth and then finish the tenon as if it were 90 degrees to that plane This gives the heel am 88.5 degree included angle to the fretboard plane.


Top
 Profile  
 
PostPosted: Wed Feb 11, 2009 4:06 pm 
Offline
Contributing Member
Contributing Member
User avatar

Joined: Mon Mar 19, 2007 7:05 am
Posts: 9191
Location: United States
First name: Waddy
Last Name: Thomson
City: Charlotte
State: NC
Focus: Build
Status: Semi-pro
Ignatio Fleta was a classical builder of note. Built a few for Segovia, and John Williams played a Fleta for years, until he switched to a Smallman. Fleta guitars are still being made by his sons. The old man died in 1977. He used a Mortise and Tenon in his construction.

_________________
Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars


Top
 Profile  
 
PostPosted: Wed Feb 11, 2009 4:18 pm 
Offline
Old Growth Brazilian
Old Growth Brazilian

Joined: Tue Dec 28, 2004 1:56 am
Posts: 10707
Location: United States
bad thing is i have read this many times, years ago but for some rason it did not stick :oops:


Top
 Profile  
 
PostPosted: Wed Feb 11, 2009 9:05 pm 
Offline
Koa
Koa
User avatar

Joined: Thu Mar 30, 2006 4:33 am
Posts: 1518
Location: Canada
Michael I was definitely showing my ignorance, because I was just asking about generic neck fitting using a 2deg (1.5) angle.... I completely missed the Fleta thing and so I apologize if I sorta threw the subject off track...
Im not sure if the fleta construction of a mortise and tenon is a unique M&T method, compared to standard M&T construction -
Hesh has kindly offered to clear up my confusion in PMs
Cheers
Charlie


Top
 Profile  
 
PostPosted: Wed Feb 11, 2009 9:53 pm 
Offline
Contributing Member
Contributing Member
User avatar

Joined: Thu May 12, 2005 5:46 am
Posts: 2997
Location: United States
Hi Rond and welcome to the forum.
You can simply set a sliding bevel angle to the appropriate angle and scribe the lines to cut to.

I have a neck jig that I use to do mine however that's adjustable to the appropriate angle. This is set up for steel strings though and not classical's as they have a forward tilt on the neck, not a back tilt. I have built in the Fleta style also, so when I need to do a forward tilting neck I set the fixture to 90 degrees and place a small shim under the tenon area of the neck to provide the appropriate angle for the forward tilt.
Hope that helps. You probably want to scribe the line and cut to that.


You do not have the required permissions to view the files attached to this post.

_________________
Jim Watts
http://jameswattsguitars.com


Top
 Profile  
 
PostPosted: Thu Feb 12, 2009 8:18 pm 
Offline
Walnut
Walnut

Joined: Thu Mar 13, 2008 8:58 am
Posts: 6
Location: Haileybury, Ontario, Canada
It's definitely empirical work for me.
I will have to work very carefully.
Thanks for the replies.
Ronald


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 8 posts ] 

All times are UTC - 5 hours


Who is online

Users browsing this forum: No registered users and 16 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Jump to:  
Powered by phpBB® Forum Software © phpBB Group
phpBB customization services by 2by2host.com